The study investigated that patients with chronic conditions, including heart failure and high blood pressure at the time of their heart attack, were more likely to die sooner.
Researchers say although there are guidelines covering how patients who have had a heart attack should be treated, they do not extend to people with multimorbidity and individuals with two or more pre-existing illnesses. And the lack of specific guidelines may explain why some patients are dying earlier.
Dr. Marlous Hall, from the Leeds Institute of Cardiovascular and Metabolic Medicine, said, “Now we have an idea of how certain chronic conditions group together in heart attack patients, we can target those groups of diseases – to try and improve treatment options.
“Previous research has focused on the interplay between heart attack and single long-term conditions but as the population gets older, more and more people who experience a heart attack are already suffering from a number of other illnesses.
“Further research needs to focus on the way those other illnesses may complicate recovery from a heart attack.”
The study set out to examine how multimorbidity impacted survival after a heart attack by analyzing the records of almost 700,000 people in England and Wales who had a heart attack.
Almost 60 percent of those patients had at least one pre-existing health condition at the time of their heart attack.
The researchers looked at the association between seven common chronic diseases and mortality rates following a heart attack. Those conditions were diabetes, chronic obstructive pulmonary disease or asthma, heart failure, kidney failure, a stroke, high blood pressure and peripheral vascular disease (narrowing of the blood vessels outside of the heart and brain).
After going through a statistical modeling technique called latent class analysis, the specialists were able to group the patients into three groups based not only on the number of pre-existing conditions they had but also on the way those conditions clustered with one another. The three groups were high, medium and low multimorbidity.
Patients were followed up for eight years following their heart attack.
The analysis showed that people in the high multimorbidity group were likely to have heart failure and high blood pressure and peripheral vascular disease prior to their heart attack.
Half of these patients had died within four and a half months, and overall, they were 140 percent more likely to die over the study period following a heart attack compared to those with few or no multimorbidities.
People in the medium multimorbidity group were likely to have peripheral vascular disease and high blood pressure, with a smaller proportion of patients having other conditions.
Half of these patients had died within six and a half months, and overall they were 50 percent more likely to die over the study period following a heart attack compared to those with few or no multimorbidities.
The team likewise looked at whether patients received the standard medical treatment following a heart attack – which includes aspirin, beta-blockers, and statins.
After removing those patients who were not eligible for drug therapy due to their medical history for instance – 3 percent fewer patients in the high multimorbidity group received aspirin compared to medium and low multimorbidity groups.
In terms of beta blockers, the picture was starker, with 6 percent fewer patients in the high multimorbidity group getting the drug compared with the medium and low groups. With statins, 5 percent fewer patients in the high multimorbidity group got them compared to the medium and low groups.
Dr. Hall said, “Patients in the high multimorbidity group experienced a greater chance of dying sooner.
“One possible explanation for this is that some of these patients were not getting the standard drug therapy following a heart attack. But it is also likely that poorer outcomes result from the fact that there are no specific guidelines about how to treat these groups of conditions together.”
Professor Jeremy Pearson, Associate Medical Director at the British Heart Foundation, said, “As the population gets older, more and more people who experience a heart attack are already suffering from a number of other illnesses.
“We need to make sure that we’re providing the best possible care for people with these conditions, to both reduce their chance of having a heart attack and to give them the best possible chance of recovering from a heart attack should the worst happen.”
The study was published in the journal PLOS Medicine.